In a future airspace management system for unmanned and manned airspace users - especially when enabling flights in urban areas - a large number of constraints and requirements must be considered in order to ensure a safe and efficient integration of new airspace users. These airspace users can be very diverse and include, in addition to VFR traffic, also other participants such as personal air vehicles, cargo UAS, parachute jumpers, weather balloons or prioritizing air traffic, e.g. rescue helicopters. In addition to aspects relating to different UAS/PAV design, performance and capabilities, further requirements for protecting flight areas (so-called geo-fencing) or board autonomous flights are to be considered in an urban ATM concept. In ...